Can I be fired for something posted on Facebook?

I work at papa johns, I've driven for them for about a week. I have my Facebook set to friends of friends, and had no coworkers added as friends. However, I had a friend in common with one of them so she could still see my post. I had said something along the lines of "bathrooms at work are great, you can sit on your phone and none of the d*cks out there think anything of it. " she then commented "just your boss , but okay, thanks. " could I legally be fired for saying something on my own personal account and never addressing that it was papa johns I was even talking about?